When I did mine I packed as much grease onto the shaft via the greaser turning the shaft by hand. Loosened nuts etc, removed the old packing and inserted the pre cut new pieces. Having re fitted and tightened the nuts {finger tight] I Tightened the nuts two flats at a time alternately until the shaft was just free and not binding.......I found that the grease was enough to hold back the water, just make sure you squeeze in as much as you can whilst turning the shaft...............not one drop of water spilt.

after about two years the fan ran increasingly slower.......I tried cleaning...adjusting motor position....oiling....all with no lasting result......as I said I bought a new motor [from Shobnal Marina]...since then it has worked fine.....I may be wrong but I thought the heat was killing the motor magnets.?